Calculating device



Feb. 14, 1928.

R. S. DREW ET AL CALCULATING DEVICE Filed June 2l, 1926 ff@ and@ Z'S mmm.\% mm N SN f Patented Feb. 14, 1928.

Unirse stares PATENT GFTQF..

ROBERT S. DREW, OF EVANS'IGN, Alfil) CURTIS L. CRUVER, GF OAK PARK,ILLINOIS, ASSIGNORS TO CRUVER IvIANUIAC'IURIl'G COMPANY, 035 CHICAGO,ILLINOIS, A

CORPORATION' yOF ILLINOIS.

CALCULATING DEVICE.

Application filed. June 21,

rlhis invention has for its object to provide a simple and compactdevice for quickly and accurately ascertaining mathematical `resultssuch as the rate of per centof dividends or interest yielded bysecurities at prices other than par where the lined rate is based on parvalue, or to ascertain the yield to maturity of bonds from date ofpurchase based on price paid therefor and for similar purposes, thepresent invention relating solely to the structural characteristics ofthe device whereby compactness is obtained.

In the accompanying drawings illustrating the preferred embodiment ofthe invention:

Fig. l is a front elevation of a calculating device constructed inaccordance with the invention.

Fig. 2 is a. longitudinal section of the saine on the line 'QL-2 of Fig.l.

F ig. 3 is a perspective view of an operative element of the device. i

The device comprises a pocket member l, made preferably of a tough,flexible material such as pyroXilin, which is flat and is open only atthe top. Said pocket member contains the card 2 which rpreferably' is ofgreater length than said member l, so that itprojects from the lattersutiiciently to be easily digitally engaged for extraction. rl"he rearwall of the pocket member l is preferably provided with the projectionsat opposite ends extending to such height as to bring` their outer ortop edges flush with the outer edge of the card 2 when the latter isdisposed at the inner limit of its movement, the recess el midwaybetween the said project-ions 3 permitting access to the rear face ofthe card for purposes of digital engagement as aforesaid. rllheprojections 3 serve mainly to afford support for the projecting edgeportion of the card 2 to minimize chance bending or breaking thereof.

The card 2 is provided on its front face with columns of iigures andgraduations printed or otherwise impressed thereon and disposed usuallyto substantially cover the entire surface thereof from one side edge tothe other, the nature of these figures being 1926. Serial No. 117,245-

dependent upon theparticular nature of the information which the deviceis intended to yield.

Associated with the card 2 for purposes of yielding such information isa sliding member 5 consisting of a flat rectangular piece of materialpreferably of the same kind as that of which the members l and 2 arecomposed, the upper edge of said member 5 being preferably flush withthe upper edge of the front wall of the member l. The said front wall isprovided 'with a transverse slot 6 extending from a point adjacent toand spaced from one side edge of' said member l to a point adjacent andspaced from the other side edge thereof.

plate 7 disposed within the member l and provided between its ends andside edges with two pairs of opposed L-shaped flanges S. the Shanks ofwhich pass through the slot 6 and also through the longitudinal slot 9of the member 5, serves to operatively associate the member 5 with themember l. The slot 9 in the member 5 is of such length as to be slidablerelatively to the plate T and the latter is slidable within the memberl, these movements being transversely of the columns of figures ou thecard and of the direction of movement of the latter relatively to themember l.

The member 5 is provided along its upper edge with a graduated scale,one of said graduations consisting of the representation of anarrow-head and constituting what may be termed the zero pointl fromwhich the graduated scales at the rightand left thereof begin. Toascertain quickly a given fact or the answer to a mathematical problemwhich the device is adapted for, the card 2 extracted until a certainhorizontal row of iigures appears immediately above the upper edge ofthe member 5. The latter is then moved until the arrow-head thereonregisters with a certain column of figures on the card 2, whereupon theresult is given, the details of this calculation or operation beingwholly immaterial to the structural characteristics of the invention andbeing partly described only to accentuate the important feature of thelatter, which is, that by reason of the plate 7 connecting the member 5with the member l, the saidmember can be moved suiiiciently relativelyto the member l to bring the arrow-head into register with either sideedge of the card 2. Thus the length of the member 5 can be limited toequal the Widtlrof the member l and the card 2 be completely coveredWith columns offiguresfromone'sideedge to the other. f,-hovvever, themember 5 did notliave suoli along movement proportionate toits ownlength, then it would obviously necessitate a card 2 andcont-ainer l ofgreater VWidth and the Waste of marginal spacesat the side edge portionsof the card l,`or, "as an alternative, vthe'member 5 Would have to be ofsuch greater length than the Width of the members l and2 as to projectat its ends beyond the side edgesof said members. The disadvantages ofthe tivo lastmentioned re- L quirements in event of omission of theplate 7 vdue to increase iny size of; members l, 2 and `5, or of the,member 5 only, is easily apparent. l Y Y Y Y Y v e lVlien the card 2 isdisposed at the inner limit of its movement and the member disposed Withits tend edges flush witlrthe side Y edges of themember 1,-the device isthin,

fiat andrectangular, so as to be easily carried in a coat pocket Withoutdanger of disscale into register with yany desiredgure ony the card. Y Yj Y .Y

2. In combination, a `fiat envelope-like receptacle open at one side, acard bea-ring columns of figures covering theentire surfaceV thereof,snugly Vfitting said` receptacle and adapted to be caused to projecttherefrom to bring any' desiredrigure: on said card into positionimmediately outwardly the open side of the receptacle, a memberbearing-a graduated scale along onev edge Vdisposed Vexternally of saidreceptacle with the last-named edgeV thereofl substantially flush withthe open yend of said receptacle, said memberbeing of nogreater lengthVthan the Width of said receptaclezand slidably associated with thelatter for movement transversely ofthe movement .of said card, theklimits of sliding movement of said member being such thata givenVgraduation betiveenthe ends of the same may be Vbrought to register withany figure on the card.V

thereof,

ln combination, a flat envelope-like receptacle openl at one side, acard bearing columns` of figures covering the entire surface adapted tobe caused to project therefrom coloring any desired figure on said cardinto position immediately outwardly the open side of the receptacle,member bearing a graduated scale along one edge disposed externally ofsaid receptacleJ With` the-*lastnamed edge thereof substantially flushwith the open end of said receptacle, said member being of no greaterlengthV than the Width of said receptacle, means operatively engagedwith said member and said receptacle for slidably associating saidmember with the latter for movement transversely of Y ysaid cardandproviding a length of movement sufficient toI bring a given graduationof said member into register with any desired figure on said card. i

. rlhecombination with a receptacle and lcard of the kind-specified, ofa device slidably associated with they receptacle formovement-transversely of the direction of movenient of said card, andamemberV for cooperation With the card slidably associated 5. Thecombination with a receptacleand in the snugly fitting said receptacleandV card of thel kind speciiied, Vthe receptacle provided in one wallwith a slot parallel ivithfthe open end thereof, of aplate'disposedivthin the receptacle, E -shaped flanges on said platehaving their shanlrs projecting through said slot andro-operating withthe latter to guide said plate in recipi'ocatory movement relatively tothe receptacle, and

a longitudinally slotted member. engaged with said flanges and disposedexternally of said receptacle for movement relatively to the latter andsaid plate. j

6. The combination with Aa card of the kind-specified, and anenvelope-like receptacle therefor open at the top, of a. member disposedexternally of the receptacle for movement parallel with the open end vofthe latter, there being aligned guide slots in said member and a ivalloff the receptacle, aplate disposed Within the. latter, and L-shapedflanges on saidplate havingtheirslianks projecting through andco-operating Vwith both said slots for guiding saidmember,4

the outer end portions of said flanges en-Y gaging the outer face ofsaid member.

V7. The combination ivit-liV aV card of thel kindv specified, and anenvelope-like receptacle thereforopen at the top, .of a member disposedexternally of the receptacle forl movement parallel with the open lendofthe latter, there being` aligned guide slots in said member and a Wallof the-receptacle, a plate,

disposed Within the latter, and Lshaped flangeson said plate havingtheir Shanks projecting through and rco-operating with both said slotsfor guiding said member, the outer end portions of said anges engagingthe outer face of said member, the length of said member being nogreater than the Width of the receptacle and the flanges of said platespaced and arranged, and the length of said slots being relatively suchthat by co-operation with said langes said member may be moved to bringa given point between the ends thereof into regis- 10 ter with eitherside edge of said card.

ROBERT S. DREW. CURTIS L. CRUVEH.

